The Department of Pathology maintains and operates a state-of-the-art specific pathogen free (SPR) facility in the north wing of the Medical Sciences Building of the University of Florida Health Sciences Center. All mice brought into this new facility are SPR or are re-derive by embryo transfer into SPF females of another strain. Establishing all experimental mice in an SPF environment is a great advance in controlling environmental factors that could affect the pathogenesis of diabetes and immunologic function. The facility is staffed with personnel with several years of experience in maintaining SPF conditions, in animal husbandry, and in breeding and maintaining NOD mice. All animals are house in micro-isolator cages. The facility has an electronic inventory data base available to all University of Florida investigators. The facility assists investigators in the maintaining existing strains of mice and developing new lines, e.g. congenic mice. We have considerable experience in this practice. The PI and co-Investigator are the Director and Associate Director of this facility. The Diabetes Program Project Mouse Core will provide the necessary SPF mice, resources, and environment to carry out studies related to the immunogenetics of type 1 diabetes. The mouse colony Core will increase the availability of NOD and other strains of nice needed for the proposed project. In support of the Program Project, the mouse core facility will: 1) Maintain and breed new B6.NOD subcongenic mice. 2) Provide necessary C57BL/6, NOD, NODscid/scid, NOD congenic, transgenic and knockout strains and C57BL/6 mice. 3) Provide genotyping services to in relationship to the evaluation of existing congenic, transgenic and knock-out mice for the development of new polycongenic mouse strains.